6-month Progression-Free Survival (PFS6) as a prognostic factor in large B-cell lymphoma patients undergoing chimeric antigen receptor T-cell therapy: A real-world multicenter study

Chimeric antigen receptor T-cell (CAR-T) therapy has significantly improved overall survival (OS) in relapsed or refractory large B-cell lymphomas (R/R LBCL). However, factors associated with outcomes of CAR-T cell therapy in patients with R/R LBCL have not been fully elucidated. And limited evidence supports the use of early endpoints to evaluate the efficacy and long-term survival. Progression-free survival (PFS) at 6 months (PFS6) was defined as being alive and free of relapse or progression within 6 months of CAR-T cell infusion. We aimed to assessed OS stratified by PFS6 by analyzing data from 71 R/R LBCL patients treated with CAR-T therapy across 2 hospitals. Subsequent OS was defined from the time of PFS6 or progression within 6 months to death. Among them, 58% reached PFS6. Compared with patients failed to achieve PFS6, 1-year OS was 91.3% vs. 40.2% and 2-year OS was 91.3% vs. 32.1%, respectively. Patients achieving PFS6 had excellent outcome, whereas patients exhibiting earlier progression had a poor survival. Key predictors of PFS failure included older age (> 60) (P = 0.040, OR:3.40, 95%CI:1.06–10.93), lower pretransfusion hemoglobin level (P = 0.019 OR:0.27, 95%CI:0.09–0.81), and higher IFN-ʏ level (P = 0.022, OR:2.00, 95% CI:1.66–4.08). This insight could aid in risk stratification and support the use of PFS6 as a surrogate endpoint in clinical trials.